Ballast IC makes for brighter fluorescent lamps

Lexington, Mass.—STMicroelectronics says its L6585 "combo IC," which integrates a power factor correction stage with a half-bridge controller and all the relevant drivers and logic for an electronic ballast IC, delivers higher efficiency and thus ultimately makes for fluorescent lamps that shine brighter.

As well as a one-chip solution that eliminates a slew of external components that would normally be required by traditional combo ICs, it's also the first such solution, according to the company, to enable end-of-life detection in either "lamp-to-ground" or "block capacitor to ground" ballast configurations.

The L6585 features independently programmable pre-heating and ignition duration as well as the half-bridge frequencies for each operating phase. As a result, this IC serves many different lamp types. In addition, the voltage applied to the lamp is limited to a constant value during the ignition phase.

Other lamp protection features include circuitry for detecting over-voltage and disconnection of the PFC's feedback loop. A highly linear multiplier allows wide-range-mains operation and extremely low total harmonic distortion. Lamp management is simplified by an automatic re-lamp feature, which allows operators to replace lamps without needing to power off any other lamps.

Click here for the product datasheet. Offered in the SO20 ECOPACK package, the L6585 is priced at $1.40 each in 10k quantities. Samples of the combo IC are available now and volume production is scheduled for January.